tell your doctor about all medical conditions and medications. do not use if you have prostate or breast cancer. serious side effects could include increased risk of prostate cancer; worsening prostate symptoms; decreased sperm count; ankle, feet, or body swelling; enlarged or painful breasts; problems breathing while sleeping; and blood clots in the legs. common side effects include skin redness or irritation where applied, increased red blood cell count, headache, diarrhea, vomiting, and increase in psa. see your doctor, and for a 30-day free trial, go to axiron.com.